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infectious disease, early 14c., plural of Middle English masel, perhaps from Middle Dutch masel "blemish" (in plural "measles") or Middle Low German masele, from Proto-Germanic *mas- "spot, blemish" (cf. Old High German masla "blood-blister," German Masern "measles").
There might have been an Old English cognate, but if so it has not been recorded. Form probably influenced by Middle English mesel "leprous" (late 13c.).
measles mea·sles (mē'zəlz)
An acute contagious viral disease usually occurring in childhood and characterized by eruption of red spots on the skin, fever, and catarrhal symptoms. Also called rubeola.
Any of several other diseases, especially German measles, that cause similar but milder symptoms.
A disease of cattle and swine caused by tapeworm larvae.